Just thought I'd share a couple of hairbands I've made. I made the cable one some time ago for myself - really simple: two stitches of garter stitch either side with an eight stitch cable (4+4) in the middle, knitted until it was long enough to fit then joined the ends.
The one on the right I made for DD's birthday earlier this month. The ends are garter stitch and the main part is linen stitch, which I saw on Ravelry and thought would make a nice hairband. Unfortunately the linen stitch doesn't really show up very well in the photo, which just looks stripy, but closer to it can be seen that the colours kind of dip into each other, due to the stitch. Perhaps sock yarn wasn't the best choice for this stitch, but we liked the colours. The yarn was left over from my first socks (post below somewhere) and the button was one I happened to have lurking in my needlework stuff.
(WIPs still progressing but not ready for blog yet. Also need to get started on Rudolf...)